Hardware Mpeg2 encoding VS Software

Besides speed are there advantages to using a hardware encoder. I do a lot of high speed films, On-ride coaster videos etc. I need something that will keep the quality consistent while the action is moving fast.
If hardware is the answer, does anyone have any suggestions or recommendations. Is there such a thing as Mpeg2 encoders under 1000.00

I seriously doubt the usefulness of MPEG-2 hardware encoder, since the facts are that by using 2-pass (or multipass) VBR encoding, you achieve better results in terms of video quality/size of the video file. Obviously if the size is not a problem, then 1-pass VBR encoding, where you can't predict the video's physical size in the end, can be done with hardware encoding. 2-pass is impossible to do with realtime, since it requires analyzing of the whole video stream in order to find the "difficult" and "easy" parts of the video and adjusting the required bandwidth for each frame based on those factors.